JP3056716B2 - Construction Machine Main Frame - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a construction machine, and more particularly to a main frame of a bulldozer.

[0002]

2. Description of the Related Art Conventionally, construction machines (particularly, bulldozers)
The front part of a pair of left and right main frames that constitute the main part of the vehicle body has a lift cylinder support portion that supports one end of a lift cylinder that vertically moves a work machine (a blade in a bulldozer). I have. In addition, a cross member that supports an equalizer bar that connects a pair of left and right track frames around which the traveling crawler is wound so as to be vertically swingable connects the pair of left and right main frames. In the inside frame type in which the left and right ends of the working machine frame (U-shaped or C-shaped frame) to which the working machine is attached are located between the left and right main frames and the track frame, the working machine frame is A work machine frame support portion that is swingably supported in a vertical direction is provided at a front portion of the main frame. In the outside frame type in which the left and right ends of the working machine frame are located outside the left and right track frames, the working machine frame support is provided outside the track frame. The rear of the pair of left and right main frames includes a steering device, a mounting surface for a power unit (such as a final reduction gear cover) and a mounting surface for a support member of a traveling device (such as a truck frame). The steering case is welded to form an integral structure. The steering case is made of a sheet metal welded structure or a cast steel workpiece.

[0003] An external force applied to the blade during work acts on the main frame via the work machine frame and the lift cylinder. Therefore, it is necessary that the main frame has strength enough to withstand the external force and sufficient rigidity, and various proposals have been made on the main frame structure for this purpose. As such a main frame structure, for example, those disclosed in Japanese Utility Model Laid-Open Publication No. 2-88877 and Japanese Patent Publication No. 62-24585 are well known.

FIG. 5 is a perspective view showing a main frame structure disclosed in Japanese Utility Model Laid-Open No. 2-88877, and FIG. 6 is a side view showing a state in which a working machine frame is attached to the main frame. As shown in the figure, a main frame (corresponding to a main frame of the present application, hereinafter referred to as a main frame) 71 is divided into a pair of main frame front portions 72 and a pair of main frame rear portions 73, and a crossbar is provided. 74 (referred to as a cross member) is a front plate 75 and a rear plate 7
6 are joined by members 77a, 77b, 77c that join them. The main frame front portion 72 is attached to the front plate 75 of the cross member 74 in a state where the main frame front portion 72 is narrower than the main frame rear portion 73 and is offset inward, while the rear member 76 of the cross member 74 is attached to the main frame rear portion 73. Is attached. Further, the front plate 75 of the cross member 74 supports the work implement bracket 33 (the work implement frame 32 to which the blade 31 is attached) on the outside of the main frame front part 72 in a swingable manner. The work machine frame support member 5 is attached by bolts, and a cylinder bracket 79 (for supporting the lift cylinder 34 so as to swing freely) is provided on the upper surface of the main frame rear portion 73. 6
Are attached by bolts. Also,
The equalizer bar 20 is swingably mounted between the front plate 75 and the rear plate 76 of the cross member 74, and the member 77 b regulates the swing amount of the equalizer bar 20. The rear portion 73 of the main frame is formed in a box shape by a plate as can be seen in the figure.

[0005]

However, the above-mentioned conventional main frame structure has the following problems. 1) Between the left and right mainframes, engines, transmissions, and various hydraulic devices and electronic devices for controlling these devices and working machines are mounted. Accompanying this, these devices and devices have become larger and have more points. Therefore, it is required to increase the inner width dimension of the left and right main frames. However, if the cross section of the main frame is box-shaped or the plate thickness is increased as in the conventional case, the width of the main frame is increased, so that the overall width of the vehicle is increased in conjunction with the increase in the size of the interior, There is a problem that the weight becomes heavy. 2) In Japanese Utility Model Laid-Open Publication No. 2-88877, the cylinder bracket 79 (lift cylinder support) is located near the center of the main frame, that is, behind the rear plate 76 of the cross member 74. The work machine bracket 33 (work machine frame support) is provided below the front portion of the main frame, that is, on the front plate 75 of the cross member 74 and outside the front portion 72 of the main frame. I have. Therefore, the horizontal distance L1 (see FIG. 6) in the side view between the lift cylinder support and the work machine frame support is large. Therefore, large stress and distortion are generated between the lift cylinder support of the main frame and the work machine frame support due to the external force applied to the blade 31 during the operation. Therefore, it is necessary to reinforce this part, and since the main frame has a box-shaped cross-sectional structure for reinforcement, the structure is complicated, it takes a lot of work time for welding, the weight becomes heavy, and the overall width of the vehicle is reduced. This is a big factor. 3) Since the main frame and the stearin case provided at the rear portion are welded and integrated, the overall size is very large. For this reason, when machining the mounting surface of the power device, the traveling device, and the like of the steering case, a large-sized machining machine is required, and the operation becomes difficult.
In order to avoid this, if the main frame and the steering case are welded after completing the processing of each mounting surface of the steering case in advance, thermal distortion due to welding occurs in the steering case, so that the processing accuracy of the mounting surface is ensured. Requires reworking the mounting surface. Further, since the steering case is a sheet metal welded structure or a cast steel work, there is a problem that workability is not good.

The present invention, which focuses on the above problems, is intended to reduce the weight of the construction machine and improve the productivity by increasing the inner width between the left and right main frames without increasing the overall width of the vehicle. It is intended to provide a frame .

[0007]

[Summary of the action and effects] In order to achieve the above object, the main off for a construction machine according to the present invention
The first invention of the frame is a frame for mounting and supporting an engine.
Power transmission equipment on the inside of the box and on the front wall of the box.
Construction equipment consisting of a steering case for mounting the device
In the main frame, the frame portion is
Side, each having a vertical chevron, and
Attach the vertical bolt mounting seats to the
The left and right pair of vertical plates and the cross member
It is fixed between the opposing surfaces of the pair of chevron projections to
And frame integral part of the vertical plate of the pair, the deflection
Bolt assembly so that the arm can be separated into the steering case
The configuration is such that

According to the first invention, the frame of the main frame
Between the two vertical plates and the pair of left and right vertical plates.
Fix the cross member to be connected and integrate the vertical plate
The structure of the frame part compared to the conventional
Becomes easier. Therefore, the weight can be reduced, and
Easy to make. Also, this frame part and stearin
And the bolt case can be separated.
Therefore, processing and assembling can be easily performed independently of each other.
Improve productivity and change gears in the steering case
Machines, final reduction gears, pivot shafts and ROPS (Iwayu
Each mounting surface for mounting a fall protection frame
It can be processed with high precision. At this time, stearin
The welding case is welded to a pair of left and right frame parts as before.
No welding distortion occurs, for example, bolts
The above processing accuracy is maintained as it is
Can be Therefore, the machining accuracy of the mounting seat is maintained
The steering case on the rear end of the frame
As it can be assembled and assembled, work when installing the above devices
Good nature.

[0009] A second invention is a construction machine of the first invention.
In the frame, a pair of left and right vertical plates with chevron projections
On the outer side, from the lower side of the vertical plate,
The columnar body reaching the side is opposed to both ends of the cross member
It is fixed and the upper part of the columnar body is used as a lift cylinder support .

According to the second invention, the lift syringe is externally provided.
The external force acting through the damper is outside the pair of left and right vertical plates.
It is transmitted from the column fixed to the side to the cross member.
Distributed to the mainframe via cross members
You. Therefore, reduce the thickness of the vertical frame of the main frame.
The same outer width between both mainframes
The inside width can be enlarged, and the equipment such as the engine can be installed inside.
It will be easier.

A third invention is a construction machine of the second invention.
In the frame, working machine frame the lower front surface side of the columnar body
It is configured as a system support .

According to the third invention, the work machine frame is externally provided.
External force acting through the pair of left and right vertical plates
It is transmitted from the column fixed to the side to the cross member.
Distributed to the mainframe via cross members
You. Therefore, reduce the thickness of the vertical frame of the main frame.
The same outer width between both mainframes
The inside width can be enlarged, and the equipment such as the engine can be installed inside.
It will be easier.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A preferred embodiment of a construction machine according to the present invention, in which a main frame is applied, will be described in detail with reference to FIGS.

FIG. 1 is a perspective view of the main frame and the steering case, and FIGS. 2 and 3 are a side view and a plan view of the main frame and the steering case, respectively. 1, 2 and 3, a pair of left and right main frames 1 a and 1 b each composed of a single straight plate, which are disposed vertically and parallel to each other in the front-rear direction of the vehicle body, are located between both lower end portions. And a bottom plate 2 is welded and connected to the bottom plate 2 to form a ship bottom shape. A cross member 3 that supports an equalizer bar 20 that connects a pair of right and left track frames (not shown) so as to be vertically swingable is provided at a substantially central portion in the front-rear direction of the main frames 1a and 1b. It is welded to the bottom plate 2. The cross member 3 is formed of a U-shaped member that is open downward and has a U-shaped cross section. The lower end of the U-shaped member is welded to the bottom plate 2.

Also, a pair of left and right hollow box-shaped columnar bodies 4, 4 are provided on the outer surfaces of the left and right main frames 1a, 1b at positions corresponding to the positions of the cross members 3 in side view.
Is welded. As shown in FIG.
A work machine frame support member 5 for rotatably supporting a work machine frame 21 to which a work machine (not shown, a blade in the case of a bulldozer) is mounted is attached to a front surface of the work machine 4. A lift cylinder support member 6 for rotatably supporting one end of a lift cylinder 22 for raising and lowering the work machine is fixedly mounted on the upper portions of the box-shaped columnar bodies 4 and 4, and an equalizer bar 20 is provided on a lower side surface. Is provided. The height of the box-shaped columnar body 4 is determined by the traveling crawler 24.
From the upper part to the lower part of the equalizer bar 20.
In addition, the main frame 1 at the portion where the box-shaped columnar body 4 is welded.
The heights of a and 1b are substantially equal to the height of the box-shaped columnar body 4. As shown in FIG. 3, the front end faces 4a, 4a of the box-shaped columnar bodies 4, 4 and the front end face 3a of the cross member 3, and the rear end faces 4b, 4b of the box-shaped columnar bodies 4, 4 and the rear end face of the cross member 3. 3b are arranged so that their positions substantially coincide with each other. The rotation center of the lift cylinder support member 6 that supports the lift cylinder 22 is located between the front end face 4a and the rear end face 4b of the box-shaped columnar body 4 in side view, and Located substantially above the center line of the direction.

At the rear ends of the main frames 1a and 1b,
A steering case 1 in which a steering device (not shown) such as a clutch / brake device for the left and right final reduction gears is installed.
0, a pair of left and right mounting flanges 7a, 7
The mounting flanges 7a and 7b are fastened to the front surface of the steering case 10 detachably in the front-rear direction by a plurality of bolts 11. That is, the main frames 1a and 1b and the steering case 10 are configured to be separable. The tightening position of the bolt 11 is outside the main frames 1a and 1b in the left-right direction.
Workability at the time of attachment and detachment is improved.

As shown in FIG. 1, the steering case 1
A front frame 0 is provided with main frame mounting seats 12a and 12b for mounting the main frames 1a and 1b, and a transmission mounting seat 13 for mounting a transmission (not shown). A mounting seat 14 and a pivot shaft mounting seat 15 for mounting a pivot shaft supporting the track frame are provided. On the upper surface of the steering case 10, a frame (so-called ROPS) for protecting a passenger when the vehicle body falls down is provided.
R for mounting ROPS 23 (see FIG. 2)
An OPS mounting seat 16 and a steering case cover mounting seat 17 are provided. Further, a mounting seat (not shown) for mounting an attachment or the like (not shown) is provided on the rear surface.

FIG. 4 shows the rear end surfaces of the main frames 1a and 1b, that is, the mounting surface to the steering case 10, as viewed from the direction of arrows AA in FIG. As shown in the figure,
The lower ends of a pair of left and right mounting flanges 7a, 7b welded to the rear ends of the main frames 1a, 1b are joined by welding a connecting member 8.

As described above, the working machine frame supporting member 5
And box-shaped column 4 with lift cylinder support member 6 attached
Outside the main frames 1a, 1b and at the front end thereof
The positions of the surface 4a and the rear end surface 4b are cross members, respectively.
3 at almost the same position as the front and rear end surfaces 3a and 3b.
I have. Thereby, the work machine frame support member 5 is
And the external force applied to the lift cylinder support member 6 is almost
The box-shaped column 4 and the cross member 3 receive the box-shaped column.
Main frame 1 through the shape member 4 and the cross member 3
a, 1b and the bottom plate 2 are dispersed and transmitted.
The stress generated in the frames 1a and 1b is reduced. But
Therefore, the main frames 1a and 1b are made of one thin plate.
The rate can withstand enough,Simplified structure and reduced vehicle weight
Reduction of welding man-hours can be achieved.Also reduce the thickness
The inner width can be increased by means of
Even if things get bigger, it is not necessary to make the whole width of the vehicle larger.
No. A connecting portion is provided at the rear end of the main frames 1a and 1b.
The material 8 is provided, and the mounting flanges 7a and 7b are attached.
The main frames 1a, 1b and the steering
Since the base 10 is connected, the rigidity of this part increases,
It is easy to ensure processing accuracy.Main frame 1a, 1
b, the main frames 1a, 7b of the mounting flanges 7a, 7b
Stearing with bolts on the left and right sides outside the body than 1b
The front case is fastened to the front and back.
When attaching / detaching, the outside of the main frame (that is, the main frame
Between the robot and the crawler frame).
Appro for the wearing part Less interference during the training. Therefore,
Good workability and easy attachment and detachment.

On each surface of the steering case 10, the main frame mounting seats 12a and 12b and the transmission mounting seat 13 are provided on the front, the final reduction gear mounting seat 14 and the pivot shaft mounting seat 15 are provided on the left and right sides, and the upper surface is provided. ROPS mounting seat 16 and steering case cover mounting seat 17
Attachment mounting seats are provided on the rear surface. Thus, the steering case 10
Since the machined parts are concentrated on each other, and these mounting seats are arranged parallel or perpendicular to each other, machining is easy and finishing can be performed with high machining accuracy. In addition, the steering case 10 is an integrally cast product of spheroidal graphite cast iron, and has a good cutting workability and a high strength.
Can be shortened. Moreover, the main frames 1a, 1b
Since the steering case 10 and the steering case 10 are assembled with the bolts 11, the respective machining accuracy is secured in a high state without being affected by welding distortion or the like during assembly. Further, since the above-described processing can be performed independently of the steering case 10 separately from the main frames 1a and 1b, handling during the processing operation is facilitated. Therefore,
Productivity can be improved as a whole. Further, since the ROPS mounting seat 16 is provided on the upper surface of the steering case 10,
There is no direct load sharing from the ROPS 23 to the main frames 1a, 1b, so that the strength and weight of the main frames 1a, 1b can be reduced.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a configuration of a main frame and a steering case of the present invention.

FIG. 2 is a side view of a main frame and a steering case of the present invention.

FIG. 3 is a plan view of a main frame and a steering case of the present invention.

FIG. 4 is a view taken in the direction of arrows AA in FIG. 2;

FIG. 5 is a perspective view illustrating a main frame structure according to the related art.

FIG. 6 is a side view showing a state in which a working machine frame is attached to a main frame according to the related art.

[Explanation of symbols]

1a, 1b main frame, 2 bottom plate, 3 cross member, 3a, 4a front end face, 3b, 4b rear end face, 4
... box-shaped columnar body, 4c ... through-hole, 5 ... work machine frame support member, 6 ... lift cylinder support member, 7a, 7b ... mounting flange, 8 ... connecting member, 10 ... steering case,
12a, 12b: Main frame mounting seat, 16: ROP
S mounting seat.

Claims (3)

(57) [Claims] 1. A frame portion for mounting and supporting an engine.
And a power transmission device inside the box and on the front wall of the box.
Of construction machinery consisting of a steering case to be attached
In the frame, the frame portion is vertically projecting to the front side.
And a vertical bolt on the rear end
And a pair of left and right vertical plates with fixed mounting seats,
A cross member is paired with a pair of left and right mountain-shaped protrusions.
A pair of left and right vertical plates are integrated by fixing between facing surfaces
A frame part, and the frame part is
Featured that the bolts are assembled so that they can be separated
Construction equipment mainframe. 2. The main frame of a construction machine according to claim 1.
The vertical press on the outer side of the chevron of the pair of left and right vertical plates.
Column from the low side of the plate to the top of the plate
Fix the cross member opposite both ends and fix it on the columnar body.
Construction characterized in that the part is a lift cylinder support part
The main frame of the machine. 3. The main frame of a construction machine according to claim 2.
The lower front side of the columnar body is used as the work equipment frame support.
Main frame of construction machinery characterized by the following.